Revert of Remove the is_loading_ field from WebContentsImpl

content/browser/frame_host/interstitial_page_impl.h

Index: content/browser/frame_host/interstitial_page_impl.h
diff --git a/content/browser/frame_host/interstitial_page_impl.h b/content/browser/frame_host/interstitial_page_impl.h
index c03792dd63529f5fb833b8a79fa21598428a07bb..32361e881e37522f3e4d2b88f02cd771ac70fb91 100644
--- a/content/browser/frame_host/interstitial_page_impl.h
+++ b/content/browser/frame_host/interstitial_page_impl.h
@@ -271,6 +271,10 @@
   // revert it to its original value).
   bool should_revert_web_contents_title_;
 
+  // Whether or not the contents was loading resources when the interstitial was
+  // shown.  We restore this state if the user proceeds from the interstitial.
+  bool web_contents_was_loading_;
+
   // Whether the ResourceDispatcherHost has been notified to cancel/resume the
   // resource requests blocked for the RenderViewHost.
   bool resource_dispatcher_host_notified_;